I do not believe there is a law about it being less than 30 days. Because each Exclusive Right to Sell Listing Agreement is unique in the terms that you and your Realtor set, it will depend on a few factors.
In NC, most of our real estate contracts can be terminated through mutual consent. If it has been less than a month and you no longer wish to have your home listed with that company you may want to be aware of what the listing firm put in Paragraph 8, section (c). The amount of time stated could be something like 30-45-60+ days - so if you take your home off the market with that agent and sell it on your own, they may be entitled to compensation IF and only IF you do not sign with another firm. (So if you're planning on trying FSBO be very aware of this!) If you're looking for another agent, I recommend asking your friends who they used and were happy with or try to interview 2-3 agent. I also do not recommend simply asking for a CMA or market analysis up-front. (You don't want every agent you speak with to know all your nitty-gritty details... because if you don't sign with them it could hurt your positioning should they bring you a buyer.)
What we do at Dickens-Mitchener is to set up a mutual interview - a 1-on-1 with the seller to determine if it is a right fit for both parties. Your time is valuable and so is ours and we want to make sure that the seller is as confident in hiring us as we are confident that the seller will work with us. You want an agent who will be straight-forward with you about pricing and who will be a knowledgeable and valuable resource throughout the process.
After reviewing the NC License Laws, the only thing I can find is that listing agreements must have a termination date. If you wish to terminate early, you would need to contact your agent about changing that date and have all parties sign. Please visit the link I have provided (NC Real Estate Commission Rules) and reveiw Chapter 93A Rule A.104 (b) for reference.
Hope this helps! Please call me if you have any further questions.
Katie Pope Githrie
Dickens-Mitchener & Associates